This invention relates to an improvement in process for recovering heads fatty acids from tall oil heads and more particularly to such process wherein said heads are treated with alkali.
In U.S. Pat. No. 3,887,537 it has been proposed to blend an aqueous solution of caustic soda with such heads and to heat the resulting mixture to a temperature of about 110.degree. C. for about 20 minutes. The heated mixture then is passed into a thin film evaporator wherein retained water and unsaponifiables are distilled off. Typically, a sufficient proportion of alkali is used to fully neutralize the heads fatty acids present, and often a small excess of alkali beyond this. The aqueous caustic soda and heads form a fairly intractable mass in such initial cooking operation, tend to foam excessively, and display poor heat transfrer characteristics resulting in localized overheating and degradation of the soap. Additionally, a dehydrated solid bottoms may form which can compound the heat transfer problem. This makes the process laborious, difficult, slow, and frequently dangerous.
Advantages of the instant improvement include the formation of an easily handled and worked reaction mixture that is highly effective for the entire treatment and the eventual recovery purpose.